Since the stone age, people have cut, scraped or otherwise abraded away portions of stones, such as cave walls, sedimentary rock tablets, and granite boulders, to engrave inscriptions and designs that the engraver intends to survive his own mortality. Today the same basic techniques as have been employed for centuries are being used to engrave hard abradable surfaces.
Engraved stones are used as grave markers, monuments, art objects, and in structures for dedication or decorative purposes. Stone surfaces can be engraved by hand cutting letters and designs with a hammer and chisel, however, more recently power engraving tools have been used. The text, symbols and designs can be formed freehand, or a pattern can be used.
The process of engraving stone is time consuming and labor intensive. In part because of the labor required, the cost of engraving a surface, such as a stone monument, is high.
Recently, in an effort to reduce costs and speed the process, sandblasting has been employed to engrave hard abradable surfaces. When sandblasting is utilized a sandblast resistant mask can be formed in situ on the hard abradable surface. One method of forming a mask is to apply a layer of sandblast resistant emulsion directly to the surface and then selectively expose the emulsion. After exposure the emulsion is developed. The surface is then washed and the regions to be sandblasted are left exposed. The mask protects those regions of the surface which are not to be engraved. Once this process is initiated it must be carried forward quickly. Sandblasting, or hand engraving can then be done through the mask.
Alternatively, a precut mask can be placed over the surface to be engraved. All regions of the precut mask must be interconnected and the process of preparing the mask is labor intensive.
There is a need for a method whereby a detailed free standing mask can be formed, transferred to, and subsequently used to engrave a pattern into a hard abradable surface such as marble or granite.